In Gate Driver on Array (GOA) technology, the gate driver is integrated on the array substrate such that the disposition of additional drivers such as Chip On Film (COF) at the edge of the array substrate is omitted, which can not only facilitate compaction of the array substrate but also reduce the material cost as well as the fabrication process cost.
A GOA element corresponds to a gate line on the array substrate. Specifically, the output of a GOA element is connected to the gate line and simultaneously connected to the input of another GOA element which is connected with the next scanned gate line.
Currently there are two scan methods:
The first is forward scan, which starts from the proximate end of the array substrate and scans to the distal end, with respect to the Print Circuit Board (PCB).
The second one is backward scan, which starts from the distal end of the array substrate and scans to the proximate end, with respect to the PCB.
The internal configuration of the GOA elements and layout of via holes of the GOA elements for forward scanned array substrate and backward scanned substrate are quite different during the fabrication. In this case, when fabricating the substrate using the mask process, individual masks are substantially different from each other, which make the fabrication process of low compatibility, high fabrication and design cost.